Bakery oven

ABSTRACT

For facilitating the cleaning of bakery ovens and preventing damage due to corrosion, mechanism is provided for rotating the tray cart or truck within the oven, with such mechanism being located in the top of the oven and so designed that the mechanism, when the cart is pushed into the oven, will lift the cart free of the oven floor.

United States Patent Inventor Karl Edvard Olot Dablen Bums, Sweden761,737

Sept. 23, 1968 July 27, 1971 Elelttro-Dahlen A B Buns, Sweden Oct. 6,1967 Sweden Patented Assignec Priority BAKERY OVEN 8 Claims, 6 DrawingFigs.

us.c1 107/55, 1 107/60 lnt.C|. Alibi/00 FieldolSeerdLL ..107/55,56, s7,60, 62,64; 126/19, 20,25/142 1114211142 N;34/l84-188,l94,216,2l7;2l1/7l[56] References Cited.

UNITED STATES PATENTS 3,402,683 9/1968 Till-ander et a1 107/55 3,412,69511/1968 Anderson 107/55 FOREIGN PATENTS 21,205 1/1930 Netherlands 34/2041,033,894 4/1953 France 34/187 Primary Examiner-Wa1ter A. ScheelAssistant Examiner-Arthur 0. Henderson Attomey-Holman & Stem ABSTRACT:For facilitating the cleaning of bakery ovens and preventing damage dueto corrosion, mechanism is provided for rotating the tray cart or truckwithin the oven, with such mechanism being located in the top of theoven and so designed that the mechanism, when the cart is pushed intothe oven, will lift the cart free of the oven floor.

PATENTEDJUL 2 71971 SHEET 1 OF 4 FIG! lllllll HHI H PATENTEnJuLemn3,595,178

sum 2 OF 4 FIG. 2

PATENTEU JUL27 I9?! I snm u 0F 4 FIG. 4

BAKERY OVEN BACKGROUND OF THE INVENTION The presentinvention relates tobakery ovens of the type provided with a device for rotating at leastone wheeled transport truck or cart (multilayer carriage) about avertical axis.

The advantage of such an arrangement is that the articles placed on thetrays of the cart will be uniformly baked. With this known type of oven,thebaking is effected by means of heated air, which is caused to flowabout the pieces of dough. The hot air, however, removes the steamexpelled from the dough which makes the products dry thus lacking thedesired succulence. It has been proposed to eliminate this disadvantageby injecting steam into the oven in order to increase the moisturetherein. One disadvantage of this arrangement is that an appreciableamount of condensed water will be collected on the floor of the oven,andas thedevicc adapted to rotate the carts is sunk into the floor, itis open to corrosion attack. The member carrying the cart usuallyconsists of a comparatively large and heavy platform which, togetherwith the driving transmision, is located in a recess in the floor of theoven into which the'condensed water will flow. This recess must becleaned every day, which means that the heavy platform must be removed.A further disadvantage with this known design is that the level of thefloor within the oven will be considerably higher than that of thesurrounding floor thereby requiring a short ramp between the surroundingfloor and the floor within the oven. When the cart is pushed into theoven it must transverse this ramp, during which the trays on the cartwill be inclined and the dough pieces thereon will easily be displaced.

SUMMARY OF THE INVENTION The object of the present invention is toeliminate the disadvantages mentioned above, and to provide an ovenhaving a smooth floor which is easy to clean and which is locatedessentially level with the surrounding floor. A further object of theinvention is to provide a supporting means for carrying and rotating thecart which, due to its location only to a small extent, will besubjected to corrosive attack. The invention is essentiallycharacterized in the device is located in the upper part of the oven andprovided with members for connection with means at the upper part of thecart, with the member and means been designed, when interconnected, tolift the cart free of the floor of the oven.

BRIEF DESCRIPTION OF THE DRAWINGS The invention will below be describedwith reference to the accompanying drawings on which FIG. 1 shows across section through an oven according to the invention,

FIG. 2 shows a longitudinal section through the oven,

FIG. 3 shows a section through part of the oven in which a cart is aboutto contact the device,

FIG. 4 shows a section along line IV-IV of FIG. 1,

FIG. 5 shows a section through the upper part of modified design of theoven, and

FIG. 6 shows a view similar to FIG. 5 of a further modified embodiment.

DESCRIPTION OF THE PREFERRED EMBODIMENT The oven is generally denoted land comprises an insulated outer wall 2 along the inside of which apassage is fonned by means of a perforated plate 4. In the roof or top 5of the oven 1, a fan 7 driven by a motor 6 is arranged and located closeto one of the sidewalls of the oven. The fan draws air from passage 3aalong one of the vertical sides of the oven, and a number of heatingelements 8 are located in the passage for forcing and the air to thepassageBb at the opposite vertical sidewall of the oven. From this, theair can flow into the oven through the perforations in the plate 4.

In the middle part of the top 5, is located a vertical rotatable shaft 9carried by a combined radial-axial bearing I0 at the outside of the top.The shaft 9 passes through the top 5 as well as the air passage Be. Atthe lower end of the shaft 9, which extends into the over, per se is adevice 11 fitted. The device 11 includes a yoke 12, which at its ends isconnected to a bar 13 in such a manner that the device 11 is in the formof an H.

A guiding roller 14 is fitted to each end of the bar 13 so that allrollers are located in the same horizontal plane. The shaft 9 is drivenby any suitable means such as for instance a motor 15 and bevel gearing.

The formed pieces of dough (not shown) are located on trays 16 which areplaced on a cart 17 in superimposed layers. The cart is, at its upperpart, provided with two spaced horizontal rails 18, each of which has anupper horizontal flange. The outer ends of the upper flanges are flaredaway from the cart in such a manner that they form funnellike inlets.The height of the cart 17 above floor 19 of the oven is so chosen thatthe upper flange of flared portion 20 of the rails 18 is located levelwith the upper edges of the guiding rollers 14. The distance from themain part of the rails 18, located between the flared portions 20, andthe lowermost portion of the cart, i.e. wheels 21, is somewhat less thanthe distance between the upper edges of the guiding rollers 14 and thefloor 19 of the oven. This difference corresponds to the desired liftingof the cart.

The floor 19 preferably consists of a plate or the like, which extendsoutside a door opening 22 of the oven sufficiently to permit the firstpair of rollers 14 to contact the flared portions 20 of the guidingrails 18 when the pair of hind wheels reach the extended portion of theplate. By this arrangement, a smooth connection of the cart to thedevice is obtained.

In order to limit the movement of the guiding rails 18 in relation tothe yoke 12, the latter or the bars 13, may be provided with lockingmembers 23, each of which by means of a hinge 24 is connected to theyoke. Each locking member is at its front end, provided with a hook 25terminating in a point. The driving means 15 for the device 11 isdesigned in such a manner that the empty yoke 12 will always bemaintained in a position to permit the bars 13 to be directed towardsthe door 22 of the oven. When the cart is wheeled into the oven, thelocking member 23 directed towards the opening will be swung upwards bythe flared end of the guiding rail and is in this manner brought out ofaction. When the cart has been moved sufficiently to be carried by therollers 14, and the vertical axis of the cart coincides with therotatable shaft 9, the flared end of the guiding rail 18 will contactthe point of the other locking member 23 so that further displacement ofthe cart is prevented. In this position, the hook 25 of the foremostlocking member 23 will leave the guiding rail 18, and lock this at theopposite end in such a manner that the cart is completely fixed. Bylifting one of the locking members 23, the cart may be withdrawn.

Instead of the locking members 23, the part of the guiding rails 18adapted to carry the rollers 14 in working position may be provided withrecessed portions 26 spaced a distance corresponding to the distancebetween the rollers 14, so that these, when the cart reaches the desiredposition, will sink into the recesses.

FIG. 6 shows a modified embodiment of the device 11, which is theopposite of the arrangement according to FIGS. 1-5, in that the yoke 12at each end carries a guiding rail 27. The upper part of the cart isprovided with guiding rollers 28, which mate with the rails 27. Therollers are adapted to cooperate with the lower edges of the rails. Oneend of the rail is flared downwardly whereby the lower flange of saidend is located level with the lower edge of the roller 28 when the cartrests on the floor on the oven. The end of the rail 27 remote from theflared end is provided with a locking member 29 for preventing therollers 28 from passing through the rails. The rails furthermore may beslightly inclined away from the inlet to permit the rollers 28 to slidetowards the locking member 29.

I claim:

1. In a bakery oven having sidewalls. a floor, a top and an opening inone of its sidewalls extending essentially over the total height of theoven for permitting a multilayer, wheeled cart to be pushed into andremoved from the oven, a device mounted for rotary movement in the topof the oven including a member for engaging means at the upper part ofthe cart, said member and said means being provided with complementarycomponents operable, when the cart is pushed into the oven, tointerconnect to lift the cart free of the floor of the oven and uponrotary movement being imparted to the device to transfer a rotatingmovement from the device to the cart.

2. The bakery oven according to claim 1 in which the device includes ayoke carried by the lower end of a vertical rotatable shaft passingthrough the top of the oven, said yoke, at its ends, being provided withrollers designed for cooperation with said means at the upper part ofthe cart and said means at the upper part of the cart including twospaced parallel horizontal rails, each having an upper horizontalflange, at least one outer edge of each of said rails being flared awayfrom the cart to define funnellike inlets for the rollers which, whensupported on the horizontal flanges of the rails, are locatedsufficiently high above the floor to effect the desired lifting of thecart, and means to rotate the shaft when the cart is lifted.

3. The bakery oven according to claim 2, in which a horizontal bar isprovided at each end of the yoke, and a roller mounted at each end ofeach bar.

4. The bakery oven according to claim 2 in which said shaft is locatedsubstantially centrally in the oven and said device is provided withlocking means to retain the cart in relation to the device in a positionin which the rotatable shaft coincides with the vertical axis of thecart and each locking means consists of a recessed part at anappropriate portion of each of the rails adapted to fit a roller topermit the same partly to sink therein when the cart has reached theposition desired for rotation.

5. The bakery oven according to claim 2 in which the outer edge of bothrails is provided with a funnellike inlet and each end of the yokeincludes resilient means cooperable with the inlets to fix the cart onthe rails when the cart has reached the position desired for rotation.

6. The bakery oven according to claim 1 in which the means at the upperpart of the cart includes rollers, and the device includes a yokecarried by the lower end of a vertical rotatable shaft passing throughthe top of the oven, said yoke, at each of its ends, being provided witha guiding rail, each having a lower horizontal flange, at least one endof each rail being flared away from the top to define a funnellike inletfor said rollers, said rails being located sufficiently high above thefloor of the oven to effect the desired lifting of the cart when therollers are supported on the flanges, and means to rotate the shaft whenthe cart is lifted.

7. The bakery oven according to claim 6 in which each guiding rail isprovided with a funnellike inlet at one end only, and the other endbeing closed to prevent the rollers from passing 8. The bakery ovenaccording to claim 1 in which the device is provided with a verticalrotatable shaft located substantially centrally in the oven and withlocking means to retain the cart in relation to the device in a positionin which the rotatable shaft coincides with the vertical axis of thecart.

1. In a bakery oven having sidewalls, a floor, a top and an opening inone of its sidewalls extending essentially over the total height of theoven for permitting a multilayer, wheeled cart to be pushed into andremoved from the oven, a device mounted for rotary movement in the topof the oven including a member for engaging means at the upper part ofthe cart, said member and said means being provided with complementarycomponents operable, when the cart is pushed into the oven, tointerconnect to lift the cart free of the floor of the oven and uponrotary movement being imparted to the device to transfer a rotatingmovement from the device to the cart.
 2. The bakery oven according toclaim 1 in which the device includes a yoke carried by the lower end ofa vertical rotatable shaft passing through the top of the oven, saidyoke, at its ends, being provided with rollers designed for cooperationwith said means at the upper part of the cart and said means at theupper part of the cart including two spaced parallel horizontal rails,each having an upper horizontal flange, at least one outer edge of eachof said rails being flared away from the cart to define funnellikeinlets for the rollers which, when supported on the horizontal flangesof the rails, are located sufficiently high above the floor to effectthe desired lifting of the cart, and means to rotate the shaft when thecart is lifted.
 3. The bakery oven according to claim 2, in which ahorizontal bar is provided at each end of the yoke, and a roller mountedat each end of each bar.
 4. The bakery oven according to claim 2 inwhich said shaft is located substantially centrally in the oven and saiddevice is provided with locking means to retain the cart in relation tothe device in a position in which the rotatable shaft coincides with thevertical axis of the cart and each locking means consists of a recessedpart at an appropriate portion of each of the rails adapted to fit aroller to permit the same partly to sink therein when the cart hasreached the position desired for rotation.
 5. The bakery oven accordingto claim 2 in which the outer edge of both rails is provided with afunnellike inlet and each end of the yoke includes resilient meanscooperable with the inlets to fix the cart on the rails when the carthas reached the position desired for rotation.
 6. The bakery ovenaccording to claim 1 in which the means at the upper part of the cartincludes rollers, and the device includes a yoke carried by the lowerend of a vertical rotatable shaft passing through the top of the oven,said yoke, at each of its ends, being provided with a guiding rail, eachhaving a lower horizontal flange, at least one end of each rail beingflared away from the top to define a funnellike inlet for said rollers,said rails being located sufficiently high above the floor of the ovento effect the desired lifting of the cart when the rollers are supportedon the flanges, and means to rotate the shaft when the cart is lifted.7. The bakery oven according to claim 6 in which each guiding rail isprovided with a funnellike inlet At one end only, and the other endbeing closed to prevent the rollers from passing
 8. The bakery ovenaccording to claim 1 in which the device is provided with a verticalrotatable shaft located substantially centrally in the oven and withlocking means to retain the cart in relation to the device in a positionin which the rotatable shaft coincides with the vertical axis of thecart.